The present invention relates to a base for a hard disk drive and method of manufacturing the same.
There is a conventional base for a hard disk drive as shown in FIGS. 5 and 6. FIG. 5 is a plan view of a base used for casing parts of a hard disk drive and FIG. 6 is a sectional view of the base of FIG. 5.
As shown in FIG. 5 and FIG. 6, a base 101 for a hard disk drive has a recess 103 for mounting a motor and a through-hole 105 formed at the center of the recess 103.
The motor has a spindle passed through the through-hole 105 of the recess 103 of the base 101 and is fixed to the recess 103 by screws and the like. However, fixing work using screws and the like. is complicated and needs a large number of parts.
In contrast, there is a base as shown in FIG. 7. FIG. 7 is a sectional view partly showing a base 107 on which a motor 115 is mounted. The base 107 of FIG. 7 has a through-hole 109 and a motor holder 111. The motor holder 111 is formed by press and has a cylindrical shape communicating with the through-hole 109. The motor holder 111 includes two depressions 113 each having an annular shape formed by circumferentially cutting on the inner circumferential surface thereof. The motor holder 111 holds the motor 115 fitted and fixed via adhesive 117 to the inner circumferential surface thereof.
The solidified adhesive 117 engages with the depressions 113. This enables to easily and securely fix the motor 115 to the motor holder 111 without using screws and the like.
Under this structure, however, the depressions 113 must be cut additionally after press-forming the motor holder 111. This requires high dimensional accuracy to improve the machining accuracy. Namely, the quality of the base 107 greatly depends on the press accuracy, requiring highly sophisticated technique for press accuracy control.
If the cutting is carried out after plating treatment of the base 107, the base material of the motor holder 111 is exposed at the treated surface. This causes fatal adverse effect such as corrosion affecting the hard disk drive performance. Therefore, attention to the fatal adverse effect is required.
The cutting generates burrs, so measures against the burrs are also required.
As this result, manufacturing efficiency and yield of the hard disk drive may be lowered, to have a disadvantage in cost.    Patent Literature 1: Japanese Patent Application Laid-Open Publication No. 09-120669    Patent Literature 2: Japanese Patent Application Laid-Open Publication No. 08-153386